Updated stb_textedit.h from 1.20 to 1.26 (many fixes). (#5075)

This commit is contained in:
ocornut 2022-03-13 17:49:37 +07:00
parent de451d4474
commit 0cff5ac5a1
2 changed files with 479 additions and 299 deletions

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@ -63,6 +63,7 @@ Other Changes:
- Misc: Fixed IsAnyItemHovered() returning false when using navigation. - Misc: Fixed IsAnyItemHovered() returning false when using navigation.
- Misc: Added IMGUI_STB_SPRINTF_FILENAME to support custom path to stb_sprintf. (#5068, #2954) [@jakubtomsu] - Misc: Added IMGUI_STB_SPRINTF_FILENAME to support custom path to stb_sprintf. (#5068, #2954) [@jakubtomsu]
- Misc: Added constexpr to ImVec2/ImVec4 inline constructors. (#4995) [@Myriachan] - Misc: Added constexpr to ImVec2/ImVec4 inline constructors. (#4995) [@Myriachan]
- Misc: Updated stb_truetype.h from 1.20 to 1.26 (many fixes). (#5075)
- Misc: Updated stb_textedit.h from 1.13 to 1.14 (our changes so this effectively is a no-op). (#5075) - Misc: Updated stb_textedit.h from 1.13 to 1.14 (our changes so this effectively is a no-op). (#5075)
- Misc: Updated stb_rect_pack.h from 1.00 to 1.01 (minor). (#5075) - Misc: Updated stb_rect_pack.h from 1.00 to 1.01 (minor). (#5075)
- Misc: binary_to_compressed_c tool: Added -nostatic option. (#5021) [@podsvirov] - Misc: binary_to_compressed_c tool: Added -nostatic option. (#5021) [@podsvirov]

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@ -1,10 +1,19 @@
// [DEAR IMGUI] // [DEAR IMGUI]
// This is a slightly modified version of stb_truetype.h 1.20. // This is a slightly modified version of stb_truetype.h 1.26.
// Mostly fixing for compiler and static analyzer warnings. // Mostly fixing for compiler and static analyzer warnings.
// Grep for [DEAR IMGUI] to find the changes. // Grep for [DEAR IMGUI] to find the changes.
// stb_truetype.h - v1.20 - public domain // stb_truetype.h - v1.26 - public domain
// authored from 2009-2016 by Sean Barrett / RAD Game Tools // authored from 2009-2021 by Sean Barrett / RAD Game Tools
//
// =======================================================================
//
// NO SECURITY GUARANTEE -- DO NOT USE THIS ON UNTRUSTED FONT FILES
//
// This library does no range checking of the offsets found in the file,
// meaning an attacker can use it to read arbitrary memory.
//
// =======================================================================
// //
// This library processes TrueType files: // This library processes TrueType files:
// parse files // parse files
@ -37,11 +46,11 @@
// Daniel Ribeiro Maciel // Daniel Ribeiro Maciel
// //
// Bug/warning reports/fixes: // Bug/warning reports/fixes:
// "Zer" on mollyrocket Fabian "ryg" Giesen // "Zer" on mollyrocket Fabian "ryg" Giesen github:NiLuJe
// Cass Everitt Martins Mozeiko // Cass Everitt Martins Mozeiko github:aloucks
// stoiko (Haemimont Games) Cap Petschulat // stoiko (Haemimont Games) Cap Petschulat github:oyvindjam
// Brian Hook Omar Cornut // Brian Hook Omar Cornut github:vassvik
// Walter van Niftrik github:aloucks // Walter van Niftrik Ryan Griege
// David Gow Peter LaValle // David Gow Peter LaValle
// David Given Sergey Popov // David Given Sergey Popov
// Ivan-Assen Ivanov Giumo X. Clanjor // Ivan-Assen Ivanov Giumo X. Clanjor
@ -49,11 +58,17 @@
// Johan Duparc Thomas Fields // Johan Duparc Thomas Fields
// Hou Qiming Derek Vinyard // Hou Qiming Derek Vinyard
// Rob Loach Cort Stratton // Rob Loach Cort Stratton
// Kenney Phillis Jr. github:oyvindjam // Kenney Phillis Jr. Brian Costabile
// Brian Costabile github:vassvik // Ken Voskuil (kaesve)
// //
// VERSION HISTORY // VERSION HISTORY
// //
// 1.26 (2021-08-28) fix broken rasterizer
// 1.25 (2021-07-11) many fixes
// 1.24 (2020-02-05) fix warning
// 1.23 (2020-02-02) query SVG data for glyphs; query whole kerning table (but only kern not GPOS)
// 1.22 (2019-08-11) minimize missing-glyph duplication; fix kerning if both 'GPOS' and 'kern' are defined
// 1.21 (2019-02-25) fix warning
// 1.20 (2019-02-07) PackFontRange skips missing codepoints; GetScaleFontVMetrics() // 1.20 (2019-02-07) PackFontRange skips missing codepoints; GetScaleFontVMetrics()
// 1.19 (2018-02-11) GPOS kerning, STBTT_fmod // 1.19 (2018-02-11) GPOS kerning, STBTT_fmod
// 1.18 (2018-01-29) add missing function // 1.18 (2018-01-29) add missing function
@ -248,19 +263,6 @@
// recommend it. // recommend it.
// //
// //
// SOURCE STATISTICS (based on v0.6c, 2050 LOC)
//
// Documentation & header file 520 LOC \___ 660 LOC documentation
// Sample code 140 LOC /
// Truetype parsing 620 LOC ---- 620 LOC TrueType
// Software rasterization 240 LOC \.
// Curve tessellation 120 LOC \__ 550 LOC Bitmap creation
// Bitmap management 100 LOC /
// Baked bitmap interface 70 LOC /
// Font name matching & access 150 LOC ---- 150
// C runtime library abstraction 60 LOC ---- 60
//
//
// PERFORMANCE MEASUREMENTS FOR 1.06: // PERFORMANCE MEASUREMENTS FOR 1.06:
// //
// 32-bit 64-bit // 32-bit 64-bit
@ -275,8 +277,8 @@
//// SAMPLE PROGRAMS //// SAMPLE PROGRAMS
//// ////
// //
// Incomplete text-in-3d-api example, which draws quads properly aligned to be lossless // Incomplete text-in-3d-api example, which draws quads properly aligned to be lossless.
// // See "tests/truetype_demo_win32.c" for a complete version.
#if 0 #if 0
#define STB_TRUETYPE_IMPLEMENTATION // force following include to generate implementation #define STB_TRUETYPE_IMPLEMENTATION // force following include to generate implementation
#include "stb_truetype.h" #include "stb_truetype.h"
@ -302,6 +304,8 @@ void my_stbtt_initfont(void)
void my_stbtt_print(float x, float y, char *text) void my_stbtt_print(float x, float y, char *text)
{ {
// assume orthographic projection with units = screen pixels, origin at top left // assume orthographic projection with units = screen pixels, origin at top left
glEnable(GL_BLEND);
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
glEnable(GL_TEXTURE_2D); glEnable(GL_TEXTURE_2D);
glBindTexture(GL_TEXTURE_2D, ftex); glBindTexture(GL_TEXTURE_2D, ftex);
glBegin(GL_QUADS); glBegin(GL_QUADS);
@ -309,10 +313,10 @@ void my_stbtt_print(float x, float y, char *text)
if (*text >= 32 && *text < 128) { if (*text >= 32 && *text < 128) {
stbtt_aligned_quad q; stbtt_aligned_quad q;
stbtt_GetBakedQuad(cdata, 512,512, *text-32, &x,&y,&q,1);//1=opengl & d3d10+,0=d3d9 stbtt_GetBakedQuad(cdata, 512,512, *text-32, &x,&y,&q,1);//1=opengl & d3d10+,0=d3d9
glTexCoord2f(q.s0,q.t1); glVertex2f(q.x0,q.y0); glTexCoord2f(q.s0,q.t0); glVertex2f(q.x0,q.y0);
glTexCoord2f(q.s1,q.t1); glVertex2f(q.x1,q.y0); glTexCoord2f(q.s1,q.t0); glVertex2f(q.x1,q.y0);
glTexCoord2f(q.s1,q.t0); glVertex2f(q.x1,q.y1); glTexCoord2f(q.s1,q.t1); glVertex2f(q.x1,q.y1);
glTexCoord2f(q.s0,q.t0); glVertex2f(q.x0,q.y1); glTexCoord2f(q.s0,q.t1); glVertex2f(q.x0,q.y1);
} }
++text; ++text;
} }
@ -719,7 +723,7 @@ struct stbtt_fontinfo
int numGlyphs; // number of glyphs, needed for range checking int numGlyphs; // number of glyphs, needed for range checking
int loca,head,glyf,hhea,hmtx,kern,gpos; // table locations as offset from start of .ttf int loca,head,glyf,hhea,hmtx,kern,gpos,svg; // table locations as offset from start of .ttf
int index_map; // a cmap mapping for our chosen character encoding int index_map; // a cmap mapping for our chosen character encoding
int indexToLocFormat; // format needed to map from glyph index to glyph int indexToLocFormat; // format needed to map from glyph index to glyph
@ -802,6 +806,18 @@ STBTT_DEF int stbtt_GetGlyphKernAdvance(const stbtt_fontinfo *info, int glyph1,
STBTT_DEF int stbtt_GetGlyphBox(const stbtt_fontinfo *info, int glyph_index, int *x0, int *y0, int *x1, int *y1); STBTT_DEF int stbtt_GetGlyphBox(const stbtt_fontinfo *info, int glyph_index, int *x0, int *y0, int *x1, int *y1);
// as above, but takes one or more glyph indices for greater efficiency // as above, but takes one or more glyph indices for greater efficiency
typedef struct stbtt_kerningentry
{
int glyph1; // use stbtt_FindGlyphIndex
int glyph2;
int advance;
} stbtt_kerningentry;
STBTT_DEF int stbtt_GetKerningTableLength(const stbtt_fontinfo *info);
STBTT_DEF int stbtt_GetKerningTable(const stbtt_fontinfo *info, stbtt_kerningentry* table, int table_length);
// Retrieves a complete list of all of the kerning pairs provided by the font
// stbtt_GetKerningTable never writes more than table_length entries and returns how many entries it did write.
// The table will be sorted by (a.glyph1 == b.glyph1)?(a.glyph2 < b.glyph2):(a.glyph1 < b.glyph1)
////////////////////////////////////////////////////////////////////////////// //////////////////////////////////////////////////////////////////////////////
// //
@ -846,6 +862,12 @@ STBTT_DEF int stbtt_GetGlyphShape(const stbtt_fontinfo *info, int glyph_index, s
STBTT_DEF void stbtt_FreeShape(const stbtt_fontinfo *info, stbtt_vertex *vertices); STBTT_DEF void stbtt_FreeShape(const stbtt_fontinfo *info, stbtt_vertex *vertices);
// frees the data allocated above // frees the data allocated above
STBTT_DEF unsigned char *stbtt_FindSVGDoc(const stbtt_fontinfo *info, int gl);
STBTT_DEF int stbtt_GetCodepointSVG(const stbtt_fontinfo *info, int unicode_codepoint, const char **svg);
STBTT_DEF int stbtt_GetGlyphSVG(const stbtt_fontinfo *info, int gl, const char **svg);
// fills svg with the character's SVG data.
// returns data size or 0 if SVG not found.
////////////////////////////////////////////////////////////////////////////// //////////////////////////////////////////////////////////////////////////////
// //
// BITMAP RENDERING // BITMAP RENDERING
@ -1347,6 +1369,22 @@ static stbtt__buf stbtt__get_subrs(stbtt__buf cff, stbtt__buf fontdict)
return stbtt__cff_get_index(&cff); return stbtt__cff_get_index(&cff);
} }
// since most people won't use this, find this table the first time it's needed
static int stbtt__get_svg(stbtt_fontinfo *info)
{
stbtt_uint32 t;
if (info->svg < 0) {
t = stbtt__find_table(info->data, info->fontstart, "SVG ");
if (t) {
stbtt_uint32 offset = ttULONG(info->data + t + 2);
info->svg = t + offset;
} else {
info->svg = 0;
}
}
return info->svg;
}
static int stbtt_InitFont_internal(stbtt_fontinfo *info, unsigned char *data, int fontstart) static int stbtt_InitFont_internal(stbtt_fontinfo *info, unsigned char *data, int fontstart)
{ {
stbtt_uint32 cmap, t; stbtt_uint32 cmap, t;
@ -1426,6 +1464,8 @@ static int stbtt_InitFont_internal(stbtt_fontinfo *info, unsigned char *data, in
else else
info->numGlyphs = 0xffff; info->numGlyphs = 0xffff;
info->svg = -1;
// find a cmap encoding table we understand *now* to avoid searching // find a cmap encoding table we understand *now* to avoid searching
// later. (todo: could make this installable) // later. (todo: could make this installable)
// the same regardless of glyph. // the same regardless of glyph.
@ -1509,12 +1549,12 @@ STBTT_DEF int stbtt_FindGlyphIndex(const stbtt_fontinfo *info, int unicode_codep
search += 2; search += 2;
{ {
stbtt_uint16 offset, start; stbtt_uint16 offset, start, last;
stbtt_uint16 item = (stbtt_uint16) ((search - endCount) >> 1); stbtt_uint16 item = (stbtt_uint16) ((search - endCount) >> 1);
STBTT_assert(unicode_codepoint <= ttUSHORT(data + endCount + 2*item));
start = ttUSHORT(data + index_map + 14 + segcount*2 + 2 + 2*item); start = ttUSHORT(data + index_map + 14 + segcount*2 + 2 + 2*item);
if (unicode_codepoint < start) last = ttUSHORT(data + endCount + 2*item);
if (unicode_codepoint < start || unicode_codepoint > last)
return 0; return 0;
offset = ttUSHORT(data + index_map + 14 + segcount*6 + 2 + 2*item); offset = ttUSHORT(data + index_map + 14 + segcount*6 + 2 + 2*item);
@ -1774,7 +1814,7 @@ static int stbtt__GetGlyphShapeTT(const stbtt_fontinfo *info, int glyph_index, s
} }
} }
num_vertices = stbtt__close_shape(vertices, num_vertices, was_off, start_off, sx,sy,scx,scy,cx,cy); num_vertices = stbtt__close_shape(vertices, num_vertices, was_off, start_off, sx,sy,scx,scy,cx,cy);
} else if (numberOfContours == -1) { } else if (numberOfContours < 0) {
// Compound shapes. // Compound shapes.
int more = 1; int more = 1;
stbtt_uint8 *comp = data + g + 10; stbtt_uint8 *comp = data + g + 10;
@ -1841,7 +1881,7 @@ static int stbtt__GetGlyphShapeTT(const stbtt_fontinfo *info, int glyph_index, s
if (comp_verts) STBTT_free(comp_verts, info->userdata); if (comp_verts) STBTT_free(comp_verts, info->userdata);
return 0; return 0;
} }
if (num_vertices > 0) STBTT_memcpy(tmp, vertices, num_vertices*sizeof(stbtt_vertex)); //-V595 if (num_vertices > 0 && vertices) STBTT_memcpy(tmp, vertices, num_vertices*sizeof(stbtt_vertex));
STBTT_memcpy(tmp+num_vertices, comp_verts, comp_num_verts*sizeof(stbtt_vertex)); STBTT_memcpy(tmp+num_vertices, comp_verts, comp_num_verts*sizeof(stbtt_vertex));
if (vertices) STBTT_free(vertices, info->userdata); if (vertices) STBTT_free(vertices, info->userdata);
vertices = tmp; vertices = tmp;
@ -1851,9 +1891,6 @@ static int stbtt__GetGlyphShapeTT(const stbtt_fontinfo *info, int glyph_index, s
// More components ? // More components ?
more = flags & (1<<5); more = flags & (1<<5);
} }
} else if (numberOfContours < 0) {
// @TODO other compound variations?
STBTT_assert(0);
} else { } else {
// numberOfCounters == 0, do nothing // numberOfCounters == 0, do nothing
} }
@ -2107,7 +2144,7 @@ static int stbtt__run_charstring(const stbtt_fontinfo *info, int glyph_index, st
subrs = stbtt__cid_get_glyph_subrs(info, glyph_index); subrs = stbtt__cid_get_glyph_subrs(info, glyph_index);
has_subrs = 1; has_subrs = 1;
} }
// fallthrough // FALLTHROUGH
case 0x1D: // callgsubr case 0x1D: // callgsubr
if (sp < 1) return STBTT__CSERR("call(g|)subr stack"); if (sp < 1) return STBTT__CSERR("call(g|)subr stack");
v = (int) s[--sp]; v = (int) s[--sp];
@ -2212,7 +2249,7 @@ static int stbtt__run_charstring(const stbtt_fontinfo *info, int glyph_index, st
} break; } break;
default: default:
if (b0 != 255 && b0 != 28 && (b0 < 32 || b0 > 254)) //-V560 if (b0 != 255 && b0 != 28 && b0 < 32)
return STBTT__CSERR("reserved operator"); return STBTT__CSERR("reserved operator");
// push immediate // push immediate
@ -2282,6 +2319,48 @@ STBTT_DEF void stbtt_GetGlyphHMetrics(const stbtt_fontinfo *info, int glyph_inde
} }
} }
STBTT_DEF int stbtt_GetKerningTableLength(const stbtt_fontinfo *info)
{
stbtt_uint8 *data = info->data + info->kern;
// we only look at the first table. it must be 'horizontal' and format 0.
if (!info->kern)
return 0;
if (ttUSHORT(data+2) < 1) // number of tables, need at least 1
return 0;
if (ttUSHORT(data+8) != 1) // horizontal flag must be set in format
return 0;
return ttUSHORT(data+10);
}
STBTT_DEF int stbtt_GetKerningTable(const stbtt_fontinfo *info, stbtt_kerningentry* table, int table_length)
{
stbtt_uint8 *data = info->data + info->kern;
int k, length;
// we only look at the first table. it must be 'horizontal' and format 0.
if (!info->kern)
return 0;
if (ttUSHORT(data+2) < 1) // number of tables, need at least 1
return 0;
if (ttUSHORT(data+8) != 1) // horizontal flag must be set in format
return 0;
length = ttUSHORT(data+10);
if (table_length < length)
length = table_length;
for (k = 0; k < length; k++)
{
table[k].glyph1 = ttUSHORT(data+18+(k*6));
table[k].glyph2 = ttUSHORT(data+20+(k*6));
table[k].advance = ttSHORT(data+22+(k*6));
}
return length;
}
static int stbtt__GetGlyphKernInfoAdvance(const stbtt_fontinfo *info, int glyph1, int glyph2) static int stbtt__GetGlyphKernInfoAdvance(const stbtt_fontinfo *info, int glyph1, int glyph2)
{ {
stbtt_uint8 *data = info->data + info->kern; stbtt_uint8 *data = info->data + info->kern;
@ -2336,7 +2415,8 @@ static stbtt_int32 stbtt__GetCoverageIndex(stbtt_uint8 *coverageTable, int glyp
return m; return m;
} }
} }
} break; break;
}
case 2: { case 2: {
stbtt_uint16 rangeCount = ttUSHORT(coverageTable + 2); stbtt_uint16 rangeCount = ttUSHORT(coverageTable + 2);
@ -2360,12 +2440,10 @@ static stbtt_int32 stbtt__GetCoverageIndex(stbtt_uint8 *coverageTable, int glyp
return startCoverageIndex + glyph - strawStart; return startCoverageIndex + glyph - strawStart;
} }
} }
} break; break;
}
default: { default: return -1; // unsupported
// There are no other cases.
STBTT_assert(0);
} break;
} }
return -1; return -1;
@ -2383,10 +2461,8 @@ static stbtt_int32 stbtt__GetGlyphClass(stbtt_uint8 *classDefTable, int glyph)
if (glyph >= startGlyphID && glyph < startGlyphID + glyphCount) if (glyph >= startGlyphID && glyph < startGlyphID + glyphCount)
return (stbtt_int32)ttUSHORT(classDef1ValueArray + 2 * (glyph - startGlyphID)); return (stbtt_int32)ttUSHORT(classDef1ValueArray + 2 * (glyph - startGlyphID));
break;
// [DEAR IMGUI] Commented to fix static analyzer warning }
//classDefTable = classDef1ValueArray + 2 * glyphCount;
} break;
case 2: { case 2: {
stbtt_uint16 classRangeCount = ttUSHORT(classDefTable + 2); stbtt_uint16 classRangeCount = ttUSHORT(classDefTable + 2);
@ -2408,18 +2484,15 @@ static stbtt_int32 stbtt__GetGlyphClass(stbtt_uint8 *classDefTable, int glyph)
else else
return (stbtt_int32)ttUSHORT(classRangeRecord + 4); return (stbtt_int32)ttUSHORT(classRangeRecord + 4);
} }
break;
// [DEAR IMGUI] Commented to fix static analyzer warning
//classDefTable = classRangeRecords + 6 * classRangeCount;
} break;
default: {
// There are no other cases.
STBTT_assert(0);
} break;
} }
return -1; default:
return -1; // Unsupported definition type, return an error.
}
// "All glyphs not assigned to a class fall into class 0". (OpenType spec)
return 0;
} }
// Define to STBTT_assert(x) if you want to break on unimplemented formats. // Define to STBTT_assert(x) if you want to break on unimplemented formats.
@ -2431,7 +2504,7 @@ static stbtt_int32 stbtt__GetGlyphGPOSInfoAdvance(const stbtt_fontinfo *info, i
stbtt_uint8 *lookupList; stbtt_uint8 *lookupList;
stbtt_uint16 lookupCount; stbtt_uint16 lookupCount;
stbtt_uint8 *data; stbtt_uint8 *data;
stbtt_int32 i; stbtt_int32 i, sti;
if (!info->gpos) return 0; if (!info->gpos) return 0;
@ -2451,9 +2524,9 @@ static stbtt_int32 stbtt__GetGlyphGPOSInfoAdvance(const stbtt_fontinfo *info, i
stbtt_uint16 lookupType = ttUSHORT(lookupTable); stbtt_uint16 lookupType = ttUSHORT(lookupTable);
stbtt_uint16 subTableCount = ttUSHORT(lookupTable + 4); stbtt_uint16 subTableCount = ttUSHORT(lookupTable + 4);
stbtt_uint8 *subTableOffsets = lookupTable + 6; stbtt_uint8 *subTableOffsets = lookupTable + 6;
switch(lookupType) { if (lookupType != 2) // Pair Adjustment Positioning Subtable
case 2: { // Pair Adjustment Positioning Subtable continue;
stbtt_int32 sti;
for (sti=0; sti<subTableCount; sti++) { for (sti=0; sti<subTableCount; sti++) {
stbtt_uint16 subtableOffset = ttUSHORT(subTableOffsets + 2 * sti); stbtt_uint16 subtableOffset = ttUSHORT(subTableOffsets + 2 * sti);
stbtt_uint8 *table = lookupTable + subtableOffset; stbtt_uint8 *table = lookupTable + subtableOffset;
@ -2468,20 +2541,15 @@ static stbtt_int32 stbtt__GetGlyphGPOSInfoAdvance(const stbtt_fontinfo *info, i
int straw, needle; int straw, needle;
stbtt_uint16 valueFormat1 = ttUSHORT(table + 4); stbtt_uint16 valueFormat1 = ttUSHORT(table + 4);
stbtt_uint16 valueFormat2 = ttUSHORT(table + 6); stbtt_uint16 valueFormat2 = ttUSHORT(table + 6);
if (valueFormat1 == 4 && valueFormat2 == 0) { // Support more formats?
stbtt_int32 valueRecordPairSizeInBytes = 2; stbtt_int32 valueRecordPairSizeInBytes = 2;
stbtt_uint16 pairSetCount = ttUSHORT(table + 8); stbtt_uint16 pairSetCount = ttUSHORT(table + 8);
stbtt_uint16 pairPosOffset = ttUSHORT(table + 10 + 2 * coverageIndex); stbtt_uint16 pairPosOffset = ttUSHORT(table + 10 + 2 * coverageIndex);
stbtt_uint8 *pairValueTable = table + pairPosOffset; stbtt_uint8 *pairValueTable = table + pairPosOffset;
stbtt_uint16 pairValueCount = ttUSHORT(pairValueTable); stbtt_uint16 pairValueCount = ttUSHORT(pairValueTable);
stbtt_uint8 *pairValueArray = pairValueTable + 2; stbtt_uint8 *pairValueArray = pairValueTable + 2;
// TODO: Support more formats.
STBTT_GPOS_TODO_assert(valueFormat1 == 4);
if (valueFormat1 != 4) return 0;
STBTT_GPOS_TODO_assert(valueFormat2 == 0);
if (valueFormat2 != 0) return 0;
STBTT_assert(coverageIndex < pairSetCount); if (coverageIndex >= pairSetCount) return 0;
STBTT__NOTUSED(pairSetCount);
needle=glyph2; needle=glyph2;
r=pairValueCount-1; r=pairValueCount-1;
@ -2504,12 +2572,15 @@ static stbtt_int32 stbtt__GetGlyphGPOSInfoAdvance(const stbtt_fontinfo *info, i
return xAdvance; return xAdvance;
} }
} }
} break; } else
return 0;
break;
}
case 2: { case 2: {
stbtt_uint16 valueFormat1 = ttUSHORT(table + 4); stbtt_uint16 valueFormat1 = ttUSHORT(table + 4);
stbtt_uint16 valueFormat2 = ttUSHORT(table + 6); stbtt_uint16 valueFormat2 = ttUSHORT(table + 6);
if (valueFormat1 == 4 && valueFormat2 == 0) { // Support more formats?
stbtt_uint16 classDef1Offset = ttUSHORT(table + 8); stbtt_uint16 classDef1Offset = ttUSHORT(table + 8);
stbtt_uint16 classDef2Offset = ttUSHORT(table + 10); stbtt_uint16 classDef2Offset = ttUSHORT(table + 10);
int glyph1class = stbtt__GetGlyphClass(table + classDef1Offset, glyph1); int glyph1class = stbtt__GetGlyphClass(table + classDef1Offset, glyph1);
@ -2517,36 +2588,24 @@ static stbtt_int32 stbtt__GetGlyphGPOSInfoAdvance(const stbtt_fontinfo *info, i
stbtt_uint16 class1Count = ttUSHORT(table + 12); stbtt_uint16 class1Count = ttUSHORT(table + 12);
stbtt_uint16 class2Count = ttUSHORT(table + 14); stbtt_uint16 class2Count = ttUSHORT(table + 14);
STBTT_assert(glyph1class < class1Count); stbtt_uint8 *class1Records, *class2Records;
STBTT_assert(glyph2class < class2Count); stbtt_int16 xAdvance;
// TODO: Support more formats. if (glyph1class < 0 || glyph1class >= class1Count) return 0; // malformed
STBTT_GPOS_TODO_assert(valueFormat1 == 4); if (glyph2class < 0 || glyph2class >= class2Count) return 0; // malformed
if (valueFormat1 != 4) return 0;
STBTT_GPOS_TODO_assert(valueFormat2 == 0);
if (valueFormat2 != 0) return 0;
if (glyph1class >= 0 && glyph1class < class1Count && glyph2class >= 0 && glyph2class < class2Count) { class1Records = table + 16;
stbtt_uint8 *class1Records = table + 16; class2Records = class1Records + 2 * (glyph1class * class2Count);
stbtt_uint8 *class2Records = class1Records + 2 * (glyph1class * class2Count); xAdvance = ttSHORT(class2Records + 2 * glyph2class);
stbtt_int16 xAdvance = ttSHORT(class2Records + 2 * glyph2class);
return xAdvance; return xAdvance;
} } else
} break; return 0;
default: {
// There are no other cases.
STBTT_assert(0);
break; break;
} // [DEAR IMGUI] removed ;
} }
}
break;
} // [DEAR IMGUI] removed ;
default: default:
// TODO: Implement other stuff. return 0; // Unsupported position format
break; }
} }
} }
@ -2559,8 +2618,7 @@ STBTT_DEF int stbtt_GetGlyphKernAdvance(const stbtt_fontinfo *info, int g1, int
if (info->gpos) if (info->gpos)
xAdvance += stbtt__GetGlyphGPOSInfoAdvance(info, g1, g2); xAdvance += stbtt__GetGlyphGPOSInfoAdvance(info, g1, g2);
else if (info->kern)
if (info->kern)
xAdvance += stbtt__GetGlyphKernInfoAdvance(info, g1, g2); xAdvance += stbtt__GetGlyphKernInfoAdvance(info, g1, g2);
return xAdvance; return xAdvance;
@ -2621,6 +2679,45 @@ STBTT_DEF void stbtt_FreeShape(const stbtt_fontinfo *info, stbtt_vertex *v)
STBTT_free(v, info->userdata); STBTT_free(v, info->userdata);
} }
STBTT_DEF stbtt_uint8 *stbtt_FindSVGDoc(const stbtt_fontinfo *info, int gl)
{
int i;
stbtt_uint8 *data = info->data;
stbtt_uint8 *svg_doc_list = data + stbtt__get_svg((stbtt_fontinfo *) info);
int numEntries = ttUSHORT(svg_doc_list);
stbtt_uint8 *svg_docs = svg_doc_list + 2;
for(i=0; i<numEntries; i++) {
stbtt_uint8 *svg_doc = svg_docs + (12 * i);
if ((gl >= ttUSHORT(svg_doc)) && (gl <= ttUSHORT(svg_doc + 2)))
return svg_doc;
}
return 0;
}
STBTT_DEF int stbtt_GetGlyphSVG(const stbtt_fontinfo *info, int gl, const char **svg)
{
stbtt_uint8 *data = info->data;
stbtt_uint8 *svg_doc;
if (info->svg == 0)
return 0;
svg_doc = stbtt_FindSVGDoc(info, gl);
if (svg_doc != NULL) {
*svg = (char *) data + info->svg + ttULONG(svg_doc + 4);
return ttULONG(svg_doc + 8);
} else {
return 0;
}
}
STBTT_DEF int stbtt_GetCodepointSVG(const stbtt_fontinfo *info, int unicode_codepoint, const char **svg)
{
return stbtt_GetGlyphSVG(info, stbtt_FindGlyphIndex(info, unicode_codepoint), svg);
}
////////////////////////////////////////////////////////////////////////////// //////////////////////////////////////////////////////////////////////////////
// //
// antialiasing software rasterizer // antialiasing software rasterizer
@ -2970,6 +3067,23 @@ static void stbtt__handle_clipped_edge(float *scanline, int x, stbtt__active_edg
} }
} }
static float stbtt__sized_trapezoid_area(float height, float top_width, float bottom_width)
{
STBTT_assert(top_width >= 0);
STBTT_assert(bottom_width >= 0);
return (top_width + bottom_width) / 2.0f * height;
}
static float stbtt__position_trapezoid_area(float height, float tx0, float tx1, float bx0, float bx1)
{
return stbtt__sized_trapezoid_area(height, tx1 - tx0, bx1 - bx0);
}
static float stbtt__sized_triangle_area(float height, float width)
{
return height * width / 2;
}
static void stbtt__fill_active_edges_new(float *scanline, float *scanline_fill, int len, stbtt__active_edge *e, float y_top) static void stbtt__fill_active_edges_new(float *scanline, float *scanline_fill, int len, stbtt__active_edge *e, float y_top)
{ {
float y_bottom = y_top+1; float y_bottom = y_top+1;
@ -3024,13 +3138,13 @@ static void stbtt__fill_active_edges_new(float *scanline, float *scanline_fill,
float height; float height;
// simple case, only spans one pixel // simple case, only spans one pixel
int x = (int) x_top; int x = (int) x_top;
height = sy1 - sy0; height = (sy1 - sy0) * e->direction;
STBTT_assert(x >= 0 && x < len); STBTT_assert(x >= 0 && x < len);
scanline[x] += e->direction * (1-((x_top - x) + (x_bottom-x))/2) * height; scanline[x] += stbtt__position_trapezoid_area(height, x_top, x+1.0f, x_bottom, x+1.0f);
scanline_fill[x] += e->direction * height; // everything right of this pixel is filled scanline_fill[x] += height; // everything right of this pixel is filled
} else { } else {
int x,x1,x2; int x,x1,x2;
float y_crossing, step, sign, area; float y_crossing, y_final, step, sign, area;
// covers 2+ pixels // covers 2+ pixels
if (x_top > x_bottom) { if (x_top > x_bottom) {
// flip scanline vertically; signed area is the same // flip scanline vertically; signed area is the same
@ -3042,32 +3156,80 @@ static void stbtt__fill_active_edges_new(float *scanline, float *scanline_fill,
dx = -dx; dx = -dx;
dy = -dy; dy = -dy;
t = x0, x0 = xb, xb = t; t = x0, x0 = xb, xb = t;
// [DEAR IMGUI] Fix static analyzer warning
(void)dx; // [ImGui: fix static analyzer warning]
} }
STBTT_assert(dy >= 0);
STBTT_assert(dx >= 0);
x1 = (int) x_top; x1 = (int) x_top;
x2 = (int) x_bottom; x2 = (int) x_bottom;
// compute intersection with y axis at x1+1 // compute intersection with y axis at x1+1
y_crossing = (x1+1 - x0) * dy + y_top; y_crossing = y_top + dy * (x1+1 - x0);
// compute intersection with y axis at x2
y_final = y_top + dy * (x2 - x0);
// x1 x_top x2 x_bottom
// y_top +------|-----+------------+------------+--------|---+------------+
// | | | | | |
// | | | | | |
// sy0 | Txxxxx|............|............|............|............|
// y_crossing | *xxxxx.......|............|............|............|
// | | xxxxx..|............|............|............|
// | | /- xx*xxxx........|............|............|
// | | dy < | xxxxxx..|............|............|
// y_final | | \- | xx*xxx.........|............|
// sy1 | | | | xxxxxB...|............|
// | | | | | |
// | | | | | |
// y_bottom +------------+------------+------------+------------+------------+
//
// goal is to measure the area covered by '.' in each pixel
// if x2 is right at the right edge of x1, y_crossing can blow up, github #1057
// @TODO: maybe test against sy1 rather than y_bottom?
if (y_crossing > y_bottom)
y_crossing = y_bottom;
sign = e->direction; sign = e->direction;
// area of the rectangle covered from y0..y_crossing
area = sign * (y_crossing-sy0);
// area of the triangle (x_top,y0), (x+1,y0), (x+1,y_crossing)
scanline[x1] += area * (1-((x_top - x1)+(x1+1-x1))/2);
step = sign * dy; // area of the rectangle covered from sy0..y_crossing
area = sign * (y_crossing-sy0);
// area of the triangle (x_top,sy0), (x1+1,sy0), (x1+1,y_crossing)
scanline[x1] += stbtt__sized_triangle_area(area, x1+1 - x_top);
// check if final y_crossing is blown up; no test case for this
if (y_final > y_bottom) {
y_final = y_bottom;
dy = (y_final - y_crossing ) / (x2 - (x1+1)); // if denom=0, y_final = y_crossing, so y_final <= y_bottom
}
// in second pixel, area covered by line segment found in first pixel
// is always a rectangle 1 wide * the height of that line segment; this
// is exactly what the variable 'area' stores. it also gets a contribution
// from the line segment within it. the THIRD pixel will get the first
// pixel's rectangle contribution, the second pixel's rectangle contribution,
// and its own contribution. the 'own contribution' is the same in every pixel except
// the leftmost and rightmost, a trapezoid that slides down in each pixel.
// the second pixel's contribution to the third pixel will be the
// rectangle 1 wide times the height change in the second pixel, which is dy.
step = sign * dy * 1; // dy is dy/dx, change in y for every 1 change in x,
// which multiplied by 1-pixel-width is how much pixel area changes for each step in x
// so the area advances by 'step' every time
for (x = x1+1; x < x2; ++x) { for (x = x1+1; x < x2; ++x) {
scanline[x] += area + step/2; scanline[x] += area + step/2; // area of trapezoid is 1*step/2
area += step; area += step;
} }
y_crossing += dy * (x2 - (x1+1)); STBTT_assert(STBTT_fabs(area) <= 1.01f); // accumulated error from area += step unless we round step down
STBTT_assert(sy1 > y_final-0.01f);
STBTT_assert(STBTT_fabs(area) <= 1.01f); // area covered in the last pixel is the rectangle from all the pixels to the left,
// plus the trapezoid filled by the line segment in this pixel all the way to the right edge
scanline[x2] += area + sign * (1-((x2-x2)+(x_bottom-x2))/2) * (sy1-y_crossing); scanline[x2] += area + sign * stbtt__position_trapezoid_area(sy1-y_final, (float) x2, x2+1.0f, x_bottom, x2+1.0f);
// the rest of the line is filled based on the total height of the line segment in this pixel
scanline_fill[x2] += sign * (sy1-sy0); scanline_fill[x2] += sign * (sy1-sy0);
} }
} else { } else {
@ -3075,6 +3237,9 @@ static void stbtt__fill_active_edges_new(float *scanline, float *scanline_fill,
// clipping logic. since this does not match the intended use // clipping logic. since this does not match the intended use
// of this library, we use a different, very slow brute // of this library, we use a different, very slow brute
// force implementation // force implementation
// note though that this does happen some of the time because
// x_top and x_bottom can be extrapolated at the top & bottom of
// the shape and actually lie outside the bounding box
int x; int x;
for (x=0; x < len; ++x) { for (x=0; x < len; ++x) {
// cases: // cases:
@ -3989,6 +4154,7 @@ static float stbtt__oversample_shift(int oversample)
STBTT_DEF int stbtt_PackFontRangesGatherRects(stbtt_pack_context *spc, const stbtt_fontinfo *info, stbtt_pack_range *ranges, int num_ranges, stbrp_rect *rects) STBTT_DEF int stbtt_PackFontRangesGatherRects(stbtt_pack_context *spc, const stbtt_fontinfo *info, stbtt_pack_range *ranges, int num_ranges, stbrp_rect *rects)
{ {
int i,j,k; int i,j,k;
int missing_glyph_added = 0;
k=0; k=0;
for (i=0; i < num_ranges; ++i) { for (i=0; i < num_ranges; ++i) {
@ -4000,7 +4166,7 @@ STBTT_DEF int stbtt_PackFontRangesGatherRects(stbtt_pack_context *spc, const stb
int x0,y0,x1,y1; int x0,y0,x1,y1;
int codepoint = ranges[i].array_of_unicode_codepoints == NULL ? ranges[i].first_unicode_codepoint_in_range + j : ranges[i].array_of_unicode_codepoints[j]; int codepoint = ranges[i].array_of_unicode_codepoints == NULL ? ranges[i].first_unicode_codepoint_in_range + j : ranges[i].array_of_unicode_codepoints[j];
int glyph = stbtt_FindGlyphIndex(info, codepoint); int glyph = stbtt_FindGlyphIndex(info, codepoint);
if (glyph == 0 && spc->skip_missing) { if (glyph == 0 && (spc->skip_missing || missing_glyph_added)) {
rects[k].w = rects[k].h = 0; rects[k].w = rects[k].h = 0;
} else { } else {
stbtt_GetGlyphBitmapBoxSubpixel(info,glyph, stbtt_GetGlyphBitmapBoxSubpixel(info,glyph,
@ -4010,6 +4176,8 @@ STBTT_DEF int stbtt_PackFontRangesGatherRects(stbtt_pack_context *spc, const stb
&x0,&y0,&x1,&y1); &x0,&y0,&x1,&y1);
rects[k].w = (stbrp_coord) (x1-x0 + spc->padding + spc->h_oversample-1); rects[k].w = (stbrp_coord) (x1-x0 + spc->padding + spc->h_oversample-1);
rects[k].h = (stbrp_coord) (y1-y0 + spc->padding + spc->v_oversample-1); rects[k].h = (stbrp_coord) (y1-y0 + spc->padding + spc->v_oversample-1);
if (glyph == 0)
missing_glyph_added = 1;
} }
++k; ++k;
} }
@ -4044,7 +4212,7 @@ STBTT_DEF void stbtt_MakeGlyphBitmapSubpixelPrefilter(const stbtt_fontinfo *info
// rects array must be big enough to accommodate all characters in the given ranges // rects array must be big enough to accommodate all characters in the given ranges
STBTT_DEF int stbtt_PackFontRangesRenderIntoRects(stbtt_pack_context *spc, const stbtt_fontinfo *info, stbtt_pack_range *ranges, int num_ranges, stbrp_rect *rects) STBTT_DEF int stbtt_PackFontRangesRenderIntoRects(stbtt_pack_context *spc, const stbtt_fontinfo *info, stbtt_pack_range *ranges, int num_ranges, stbrp_rect *rects)
{ {
int i,j,k, return_value = 1; int i,j,k, missing_glyph = -1, return_value = 1;
// save current values // save current values
int old_h_over = spc->h_oversample; int old_h_over = spc->h_oversample;
@ -4109,6 +4277,13 @@ STBTT_DEF int stbtt_PackFontRangesRenderIntoRects(stbtt_pack_context *spc, const
bc->yoff = (float) y0 * recip_v + sub_y; bc->yoff = (float) y0 * recip_v + sub_y;
bc->xoff2 = (x0 + r->w) * recip_h + sub_x; bc->xoff2 = (x0 + r->w) * recip_h + sub_x;
bc->yoff2 = (y0 + r->h) * recip_v + sub_y; bc->yoff2 = (y0 + r->h) * recip_v + sub_y;
if (glyph == 0)
missing_glyph = j;
} else if (spc->skip_missing) {
return_value = 0;
} else if (r->was_packed && r->w == 0 && r->h == 0 && missing_glyph >= 0) {
ranges[i].chardata_for_range[j] = ranges[i].chardata_for_range[missing_glyph];
} else { } else {
return_value = 0; // if any fail, report failure return_value = 0; // if any fail, report failure
} }
@ -4132,7 +4307,7 @@ STBTT_DEF void stbtt_PackFontRangesPackRects(stbtt_pack_context *spc, stbrp_rect
STBTT_DEF int stbtt_PackFontRanges(stbtt_pack_context *spc, const unsigned char *fontdata, int font_index, stbtt_pack_range *ranges, int num_ranges) STBTT_DEF int stbtt_PackFontRanges(stbtt_pack_context *spc, const unsigned char *fontdata, int font_index, stbtt_pack_range *ranges, int num_ranges)
{ {
stbtt_fontinfo info; stbtt_fontinfo info;
int i,j,n, return_value; // [DEAR IMGUI] removed = 1 int i, j, n, return_value; // [DEAR IMGUI] removed = 1;
//stbrp_context *context = (stbrp_context *) spc->pack_info; //stbrp_context *context = (stbrp_context *) spc->pack_info;
stbrp_rect *rects; stbrp_rect *rects;
@ -4301,15 +4476,14 @@ static int stbtt__compute_crossings_x(float x, float y, int nverts, stbtt_vertex
float y_frac; float y_frac;
int winding = 0; int winding = 0;
orig[0] = x;
//orig[1] = y; // [DEAR IMGUI] commented double assignment
// make sure y never passes through a vertex of the shape // make sure y never passes through a vertex of the shape
y_frac = (float) STBTT_fmod(y, 1.0f); y_frac = (float) STBTT_fmod(y, 1.0f);
if (y_frac < 0.01f) if (y_frac < 0.01f)
y += 0.01f; y += 0.01f;
else if (y_frac > 0.99f) else if (y_frac > 0.99f)
y -= 0.01f; y -= 0.01f;
orig[0] = x;
orig[1] = y; orig[1] = y;
// test a ray from (-infinity,y) to (x,y) // test a ray from (-infinity,y) to (x,y)
@ -4371,7 +4545,7 @@ static float stbtt__cuberoot( float x )
return (float) STBTT_pow( x,1.0f/3.0f); return (float) STBTT_pow( x,1.0f/3.0f);
} }
// x^3 + c*x^2 + b*x + a = 0 // x^3 + a*x^2 + b*x + c = 0
static int stbtt__solve_cubic(float a, float b, float c, float* r) static int stbtt__solve_cubic(float a, float b, float c, float* r)
{ {
float s = -a / 3; float s = -a / 3;
@ -4410,12 +4584,7 @@ STBTT_DEF unsigned char * stbtt_GetGlyphSDF(const stbtt_fontinfo *info, float sc
int w,h; int w,h;
unsigned char *data; unsigned char *data;
// if one scale is 0, use same scale for both if (scale == 0) return NULL;
if (scale_x == 0) scale_x = scale_y;
if (scale_y == 0) {
if (scale_x == 0) return NULL; // if both scales are 0, return NULL
scale_y = scale_x;
}
stbtt_GetGlyphBitmapBoxSubpixel(info, glyph, scale, scale, 0.0f,0.0f, &ix0,&iy0,&ix1,&iy1); stbtt_GetGlyphBitmapBoxSubpixel(info, glyph, scale, scale, 0.0f,0.0f, &ix0,&iy0,&ix1,&iy1);
@ -4481,18 +4650,17 @@ STBTT_DEF unsigned char * stbtt_GetGlyphSDF(const stbtt_fontinfo *info, float sc
for (i=0; i < num_verts; ++i) { for (i=0; i < num_verts; ++i) {
float x0 = verts[i].x*scale_x, y0 = verts[i].y*scale_y; float x0 = verts[i].x*scale_x, y0 = verts[i].y*scale_y;
// check against every point here rather than inside line/curve primitives -- @TODO: wrong if multiple 'moves' in a row produce a garbage point, and given culling, probably more efficient to do within line/curve if (verts[i].type == STBTT_vline && precompute[i] != 0.0f) {
float dist2 = (x0-sx)*(x0-sx) + (y0-sy)*(y0-sy); float x1 = verts[i-1].x*scale_x, y1 = verts[i-1].y*scale_y;
float dist,dist2 = (x0-sx)*(x0-sx) + (y0-sy)*(y0-sy);
if (dist2 < min_dist*min_dist) if (dist2 < min_dist*min_dist)
min_dist = (float) STBTT_sqrt(dist2); min_dist = (float) STBTT_sqrt(dist2);
if (verts[i].type == STBTT_vline) {
float x1 = verts[i-1].x*scale_x, y1 = verts[i-1].y*scale_y;
// coarse culling against bbox // coarse culling against bbox
//if (sx > STBTT_min(x0,x1)-min_dist && sx < STBTT_max(x0,x1)+min_dist && //if (sx > STBTT_min(x0,x1)-min_dist && sx < STBTT_max(x0,x1)+min_dist &&
// sy > STBTT_min(y0,y1)-min_dist && sy < STBTT_max(y0,y1)+min_dist) // sy > STBTT_min(y0,y1)-min_dist && sy < STBTT_max(y0,y1)+min_dist)
float dist = (float) STBTT_fabs((x1-x0)*(y0-sy) - (y1-y0)*(x0-sx)) * precompute[i]; dist = (float) STBTT_fabs((x1-x0)*(y0-sy) - (y1-y0)*(x0-sx)) * precompute[i];
STBTT_assert(i != 0); STBTT_assert(i != 0);
if (dist < min_dist) { if (dist < min_dist) {
// check position along line // check position along line
@ -4519,7 +4687,8 @@ STBTT_DEF unsigned char * stbtt_GetGlyphSDF(const stbtt_fontinfo *info, float sc
float ax = x1-x0, ay = y1-y0; float ax = x1-x0, ay = y1-y0;
float bx = x0 - 2*x1 + x2, by = y0 - 2*y1 + y2; float bx = x0 - 2*x1 + x2, by = y0 - 2*y1 + y2;
float mx = x0 - sx, my = y0 - sy; float mx = x0 - sx, my = y0 - sy;
float res[3],px,py,t,it; float res[3] = {0.f,0.f,0.f};
float px,py,t,it,dist2;
float a_inv = precompute[i]; float a_inv = precompute[i];
if (a_inv == 0.0) { // if a_inv is 0, it's 2nd degree so use quadratic formula if (a_inv == 0.0) { // if a_inv is 0, it's 2nd degree so use quadratic formula
float a = 3*(ax*bx + ay*by); float a = 3*(ax*bx + ay*by);
@ -4546,6 +4715,10 @@ STBTT_DEF unsigned char * stbtt_GetGlyphSDF(const stbtt_fontinfo *info, float sc
float d = (mx*ax+my*ay) * a_inv; float d = (mx*ax+my*ay) * a_inv;
num = stbtt__solve_cubic(b, c, d, res); num = stbtt__solve_cubic(b, c, d, res);
} }
dist2 = (x0-sx)*(x0-sx) + (y0-sy)*(y0-sy);
if (dist2 < min_dist*min_dist)
min_dist = (float) STBTT_sqrt(dist2);
if (num >= 1 && res[0] >= 0.0f && res[0] <= 1.0f) { if (num >= 1 && res[0] >= 0.0f && res[0] <= 1.0f) {
t = res[0], it = 1.0f - t; t = res[0], it = 1.0f - t;
px = it*it*x0 + 2*t*it*x1 + t*t*x2; px = it*it*x0 + 2*t*it*x1 + t*t*x2;
@ -4805,6 +4978,12 @@ STBTT_DEF int stbtt_CompareUTF8toUTF16_bigendian(const char *s1, int len1, const
// FULL VERSION HISTORY // FULL VERSION HISTORY
// //
// 1.25 (2021-07-11) many fixes
// 1.24 (2020-02-05) fix warning
// 1.23 (2020-02-02) query SVG data for glyphs; query whole kerning table (but only kern not GPOS)
// 1.22 (2019-08-11) minimize missing-glyph duplication; fix kerning if both 'GPOS' and 'kern' are defined
// 1.21 (2019-02-25) fix warning
// 1.20 (2019-02-07) PackFontRange skips missing codepoints; GetScaleFontVMetrics()
// 1.19 (2018-02-11) OpenType GPOS kerning (horizontal only), STBTT_fmod // 1.19 (2018-02-11) OpenType GPOS kerning (horizontal only), STBTT_fmod
// 1.18 (2018-01-29) add missing function // 1.18 (2018-01-29) add missing function
// 1.17 (2017-07-23) make more arguments const; doc fix // 1.17 (2017-07-23) make more arguments const; doc fix